mod_cache: Optionally serve stale data when a revalidation returns a

5xx response, controlled by the CacheStaleOnError directive.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1021546 13f79535-47bb-0310-9956-ffa450edef68

1 files changed, 28 insertions, 0 deletions

diff --git a/docs/manual/mod/mod_cache.xml b/docs/manual/mod/mod_cache.xml
index a160537da4..5c3579eae8 100644
--- a/docs/manual/mod/mod_cache.xml
+++ b/docs/manual/mod/mod_cache.xml
@@ -948,4 +948,32 @@ LastModified date.</description>
 </usage>
 </directivesynopsis>
 
+<directivesynopsis>
+<name>CacheStaleOnError</name>
+<description>Serve stale content in place of 5xx responses.</description>
+<syntax>CacheStaleOnError <var>on|off</var></syntax>
+<default>CacheStaleOnError on</default>
+<contextlist><context>server config</context>
+    <context>virtual host</context>
+    <context>directory</context>
+    <context>.htaccess</context>
+</contextlist>
+<compatibility>Available in Apache 2.3.9 and later</compatibility>
+
+<usage>
+  <p>When the <directive module="mod_cache">CacheStaleOnError</directive> directive
+  is switched on, and when stale data is available in the cache, the cache will
+  respond to 5xx responses from the backend by returning the stale data instead of
+  the 5xx response. While the Cache-Control headers sent by clients will be respected,
+  and the raw 5xx responses returned to the client on request, the 5xx response so
+  returned to the client will not invalidate the content in the cache.</p>
+
+  <example>
+    # Serve stale data on error.<br />
+    CacheStaleOnError on<br />
+  </example>
+
+</usage>
+</directivesynopsis>
+
 </modulesynopsis>